KR20170059661A - Power factor improving circuit and charger for vehicle adapting the same - Google Patents

Abstract

The present embodiment includes an input terminal and an output terminal connected to the input terminal and improving power factor through the input terminal. The output terminal has a non-electrolytic capacitor formed at both sides of an electrolytic capacitor for output. A first inductor is formed between the non-electrolytic capacitor and the electrolytic capacitor. In this embodiment, the ripple current (current stress) of a PFC output terminal is reduced through a CL circuit formed on the left side of the electrolytic capacitor. An input ripple current (input current stress) of a DC-DC converter can be reduced through a LC circuit formed on the right side.

Description

 TECHNICAL FIELD [0001] The present invention relates to a power factor correction circuit, and a battery charger using the same. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present embodiment relates to a circuit for improving the power factor and an automobile charger to which the circuit is applied.

Recently, eco-friendly vehicles without pollution are attracting attention. These environmentally friendly vehicles have essentially used converters for charging high voltage into batteries. The converter requires a PFC circuit (Power Factor Correction Circuit) for voltage boosting and power factor improvement.

Since PFC circuit requires high rated voltage and large capacity, the most advantageous electrolytic capacitor is used in the package side in design.

Even if the electrolytic capacitor is small, high rated voltage and large capacity can be satisfied. However, since the liquid dielectric has a dielectric property, a decrease in reliability due to current stress (current ripple) has become a serious problem.

For example, when the battery is exposed to a large amount of ripple current, the electrolytic solution evaporates, which can no longer function as a dielectric, which ultimately leads to a reduction in the capacity of the capacitor.

In addition, the converter described above is highly vulnerable to EMC (Electro Magnetic Compatibility) because it uses a high voltage AC power source as input and accompanies high frequency switching.

Failure to develop measures against EMC could lead to a reduction in the overall commerciality of the vehicle beyond the converter alone, and seriously the risk of dissatisfaction with vehicle regulations.

1. Japanese Laid-Open Patent No. 5-204478, 2. Japanese Laid-Open Patent No. 2008-172868.

It is an object of the present invention to provide a power factor improving circuit for reducing current stress and a car charger using the same.

It is another object of the present invention to provide a power factor correction circuit for improving EMC performance and a car charger using the same.

According to one embodiment, And an output terminal connected to the input terminal and improving the power factor through the input terminal. The output stage includes a non-electrolytic capacitor formed on both sides of the output electrolytic capacitor, A first inductor is formed between the electrolytic capacitors.

The input terminal may be connected in parallel between the input power supply, the second inductor, the diode, and the IGFET circuit.

The non-electrolytic capacitor may be a film capacitor or a ceramic capacitor.

The first inductor may be coupled at both sides of the electrolytic capacitor.

The non-electrolytic capacitor and the first inductor may be connected in parallel.

According to one embodiment, an automotive charger for charging a high voltage battery, comprising: a power factor correction circuit having an input terminal and an output terminal connected to the input terminal and having an output terminal for improving the power factor through the input terminal; And a DC-DC converter connected to the output terminal for converting a first DC voltage including a sinusoidal wave output from the power factor correction circuit to an AC voltage and converting the converted AC voltage to a second DC voltage, Lt; / RTI >

The output terminal forms a non-electrolytic capacitor on both sides of an output electrolytic capacitor, and forms a first inductor between the non-electrolytic capacitor and the electrolytic capacitor.

The input terminal may be connected in parallel between the input power supply, the second inductor, the diode, and the IGFET circuit.

The non-electrolytic capacitor may be a film capacitor or a ceramic capacitor.

The first inductor may be coupled at both sides of the electrolytic capacitor.

The DC-DC converter may be a boost converter.

The non-electrolytic capacitor and the first inductor may be connected in parallel.

As described above, the present embodiment has the following advantageous effects as compared with the existing technology.

First, in this embodiment, the ripple current (current stress) at the PFC output stage is reduced through the CL circuit formed on the left side of the electrolytic capacitor, and the input ripple current (input current stress ).

Second, this embodiment allows high voltage DC link inductance balancing through coupled inductors, thereby reducing high voltage Common-Mode noise and ultimately improving EMC performance.

Third, this embodiment optimizes the capacitance of the PFC output capacitor to optimize the size of the charger and reduce the weight (mass improvement) of the charger.

Fourth, the present embodiment can reduce the size of the input / output EMC filter, thereby optimizing the size of the charger and reducing the weight (mass improvement) of the charger.

Fifthly, the present embodiment can reduce manufacturing cost because the costly input / output EMC filter of the electrolytic capacitor and the charger for output are applied by using the inexpensive filter structure.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. However, the technical features of the present embodiment are not limited to the specific drawings, and the features disclosed in the drawings may be combined with each other to constitute a new embodiment.
1 is a circuit diagram showing an example of a power factor improving circuit according to an embodiment.
2 is a circuit configuration diagram exemplarily showing an example of a car charger according to one embodiment.
FIG. 3 is a circuit diagram showing an existing power factor correction circuit in contrast to the power factor correction circuit of FIG. 1 and FIG. 2. FIG.
Fig. 4 is a circuit diagram showing a power factor improving circuit compared with the power factor improving circuit of Figs. 1 and 2. Fig.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

It is to be understood that the terms used in the following examples are used only to illustrate specific embodiments, and are not intended to be limiting.

For example, the suffix "step " disclosed in the present specification is to be given or mixed with consideration only to ease of specification, and does not have a meaning or role that is different from itself.

Furthermore, terms including ordinals such as 'first' and 'second' described in the following embodiments may be used to describe various elements, but the elements are not limited by the terms . The terms are used to distinguish one component from another.

It is also to be understood that the singular forms "a" and "an" used in the description of the various embodiments described and in the claims are intended to include the plural forms as well, unless the context clearly dictates otherwise.

It is also to be understood that the term " and / or " disclosed in the following embodiments includes any and all possible combinations of one or more of the listed related items.

It is also to be understood that the terms such as " comprises "or " forming ", as used in the following examples, mean that a constituent element can be implanted unless specifically stated otherwise. But should be understood to include additional elements.

<Example of Power Factor Correction Circuit>

1 is a circuit diagram showing an example of a power factor improving circuit according to an embodiment.

Referring to FIG. 1, the power factor correction circuit 100 includes an input terminal 110 and an output terminal 120 for power factor correction.

The input terminal 110 can control the input current or the input voltage so that the peak value of the input current follows the input voltage.

The input terminal 110 includes a power source 111, an inductor 112 connected to the power source 111, a first diode 113 connected in parallel between the power source 111 and the inductor 112, And an IGFET circuit 115 connected in parallel between the inductor 112 and the second diode 114. The second diode 114 is connected to the first diode 114 and the second diode 114,

Meanwhile, the output stage 120 is connected to the input stage 110 so as to generate a sinusoidal wave by following the input voltage of the input stage 110, thereby improving not only the power factor but also the harmonic regulation.

To this end, the output stage 120 may form an output electrolytic capacitor 121 and a non-electrolytic capacitor 122 connected to both sides of the electrolytic capacitor 121.

Since the electrolytic capacitor 121 usually has a dielectric of a widely known liquid component, reliability due to current stress (current ripple) is lowered.

Therefore, in order to prevent reliability degradation due to current stress, a non-electrolytic capacitor 122 is connected to both sides of the electrolytic capacitor 121 and a first inductor 123 is connected between the non-electrolytic capacitor 122 and the electrolytic capacitor 121 ) Can be formed.

In this case, the non-electrolytic capacitor 122 and the first inductor 123 are formed on the left side of the electrolytic capacitor 121.

The non-electrolytic capacitor 122 on the left side is connected in parallel with the input terminal 110, the first inductor 123 on the left side is connected in parallel with the left non-electrolytic capacitor 122, The first inductor 123 may be connected to the output electrolytic capacitor 121 in parallel.

If the non-electrolytic capacitor 122 and the first inductor 123 are formed on the left side of the electrolytic capacitor 121, it can serve as a CL filter of the PFC output stage 120. [ The CL filter can reduce the current stress (ripple current) caused by the electrolytic capacitor 121 described above.

Here, the left non-electrolytic capacitor 122 may be made of a film capacitor or a ceramic capacitor, and the first inductor 123 formed between the left non-electrolytic capacitor 122 and the electrolytic capacitor 121 may have a coupling structure Lt; / RTI &gt;

The reason why the left inductor 123 has a coupling structure is to improve the EMC problem.

For example, when one first inductor 123 is formed between the left non-electrolytic capacitor 122 and the electrolytic capacitor 121, a phase difference due to noise occurs between high voltages generated from the input terminal 110, The resulting high voltage Common-Mode noise can be induced to the output stage 120, which can cause serious EMC problems.

Therefore, in order to prevent the above-described EMC problem, a coupled first inductor 123 is formed between the left non-electrolytic capacitor 122 and the electrolytic capacitor 121.

On the other hand, the first inductor 123 and the non-electrolytic capacitor 122 may be formed on the right side of the output electrolytic capacitor 121.

The first inductor 123 on the right side is connected in parallel with the electrolytic capacitor 121 and the non-electrolytic capacitor 122 on the right side is connected in parallel with the first inductor 123 on the right side .

When the first inductor 123 and the non-electrolytic capacitor 122 are formed on the right side of the electrolytic capacitor 121, the first inductor 123 and the non-electrolytic capacitor 122 can serve as the LC filter of the PFC output stage 120. The LC filter can reduce the input ripple current of the DC-DC converter to be connected to the output stage 120, which ultimately can reduce the current stress (ripple current) caused by the electrolytic capacitor 121 described above.

Here, the non-electrolytic capacitor 122 on the right side can be made of a film capacitor or a ceramic capacitor, and the first inductor 123 formed between the electrolytic capacitor 121 on the right side and the non-electrolytic capacitor 122 has a coupling structure Lt; / RTI &gt;

The reason why the first inductor 123 on the right side has a coupling structure is to improve the EMC problem.

For example, when one first inductor 123 is formed between the non-electrolytic capacitor 122 on the right side and the electrolytic capacitor 121, a phase difference due to noise occurs between high voltages generated from the input terminal 110, The resulting high voltage Common-Mode noise can be induced to the output stage 120, which can cause serious EMC problems.

Therefore, in order to solve the above-described EMC problem, a coupled first inductor 123 is formed between the electrolytic capacitor 121 and the non-electrolytic capacitor 122 on the right side.

The first inductor 123 coupled to both sides of the electrolytic capacitor 121 is applied to the input terminal 110 to induce inductance between the high voltage Link (+) / (- By balancing and reducing the high-voltage common-mode noise, the EMC performance in the power factor correction circuit 100 can be improved.

<Example of charger>

2 is a circuit configuration diagram exemplarily showing an example of a car charger according to one embodiment.

2, the automotive charger 200 includes a power factor correction circuit and a DC-DC converter 230 for charging a high-voltage battery, and the power factor correction circuit includes an input terminal 210, And an output stage 220.

The input terminal 210 can control the input current or the input voltage so that the peak value of the input current follows the input voltage.

To this end, the input stage 210 includes a power source 211, an inductor 212 connected to the power source 211, a first diode 213 connected in parallel between the power source 211 and the inductor 212, 212 and an IGFET circuit 215 connected in parallel between the inductor 212 and the second diode 214. The second diode 214 is connected to the first diode 212 and the second diode 214,

Meanwhile, the output stage 220 is connected to the input stage 210 to generate a sinusoidal wave by following the input voltage of the input stage 210, thereby improving not only the power factor but also the harmonic regulation.

For this purpose, the output stage 220 may form an output electrolytic capacitor 221 and a non-electrolytic capacitor 222 connected to both sides of the electrolytic capacitor 221.

Since the electrolytic capacitor 221 usually has a dielectric of a widely known liquid component, reliability due to current stress (current ripple) is lowered.

Therefore, the non-electrolytic capacitor 222 is connected to both sides of the electrolytic capacitor 221 and the first inductor 223 is connected between the non-electrolytic capacitor 222 and the electrolytic capacitor 221 in order to prevent reliability degradation due to the current stress. ) Can be formed.

In this case, the non-electrolytic capacitor 222 and the first inductor 223 are formed on the left side of the electrolytic capacitor 221.

The non-electrolytic capacitor 222 on the left side is connected in parallel with the input terminal 210, the first inductor 223 on the left side is connected in parallel with the left non-electrolytic capacitor 222, The first inductor 223 of the output capacitor 223 may be connected in parallel with the output electrolytic capacitor 221.

When the non-electrolytic capacitor 222 and the first inductor 223 are formed on the left side of the electrolytic capacitor 221, it can serve as a CL filter of the PFC output stage 220. The CL filter can reduce the current stress (ripple current) caused by the electrolytic capacitor 221 described above.

Here, the left non-electrolytic capacitor 222 may be made of a film capacitor or a ceramic capacitor, and the first inductor 223 formed between the left non-electrolytic capacitor 222 and the electrolytic capacitor 221 may have a coupling structure Lt; / RTI &gt;

The reason why the first inductor 223 on the left side has a coupling structure is to improve the EMC problem.

For example, when one first inductor 223 is formed between the left non-electrolytic capacitor 222 and the electrolytic capacitor 221, a phase difference due to noise occurs between high voltages generated from the input terminal 210, This causes the high voltage common-mode noise to be sent to the output stage 220, which can cause serious EMC problems.

Therefore, in order to prevent the above-described EMC problem, a coupled first inductor 223 is formed between the left non-electrolytic capacitor 222 and the electrolytic capacitor 221.

On the other hand, the first inductor 223 and the non-electrolytic capacitor 222 may be formed on the right side of the output electrolytic capacitor 221.

The first inductor 223 on the right side is connected in parallel with the electrolytic capacitor 221 and the non-electrolytic capacitor 222 on the right side is connected in parallel with the first inductor 223 on the right side .

When the first inductor 223 and the non-electrolytic capacitor 222 are formed on the right side of the electrolytic capacitor 221 as described above, the first inductor 223 and the non-electrolytic capacitor 222 can serve as an LC filter of the PFC output stage 220. Since the LC filter can reduce the input ripple current of the DC-DC converter 230 connected to the output stage 220 to be described later, it is possible to ultimately reduce the current stress (ripple current) caused by the electrolytic capacitor 221 can do.

The first inductor 223 formed between the electrolytic capacitor 221 and the non-electrolytic capacitor 222 on the right side may be formed of a film capacitor or a ceramic capacitor. Lt; / RTI &gt;

The reason why the first inductor 223 on the right side has a coupling structure is to improve the EMC problem.

For example, when one first inductor 223 is formed between the non-electrolytic capacitor 222 and the electrolytic capacitor 221 on the right side, a phase difference due to noise occurs between high voltages generated from the input terminal 210, This causes the high voltage common-mode noise to be sent to the output stage 220, which can cause serious EMC problems.

Therefore, in order to solve the above-described EMC problem, a coupled first inductor 223 is formed between the electrolytic capacitor 221 and the non-electrolytic capacitor 222 on the right side.

A first inductor 223 coupled to both sides of the electrolytic capacitor 221 is applied so that an inductance is generated between the high voltage Link (+) / (-) generated from the input stage 210, By balancing and reducing the high-voltage common-mode noise, the EMC performance in the power factor correction circuit 100 can be improved.

In an exemplary embodiment, the DC-DC converter 230 is connected to the output stage 220 to convert the first DC voltage including the sinusoidal wave output from the power factor correction circuit to an AC voltage, Voltage.

The DC-DC converter 230 is preferably a boost converter.

For example, the booster converter may include, for example, four IGFET circuits 231 connected in parallel from the output stage 220, a pair of inductors 232 connected in parallel between the upper and lower IGFET circuits of the IGFET circuit 231, One end of the diode 233 is connected to the input terminal of the four diodes 233 and the other end of the diode 233 is connected to the inductor 236 And two electrolytic capacitors 235 connected to the capacitor C2.

However, the present invention is not limited to the circuit configuration of the booster converter described above. Further, if it is a converter for power factor improvement and voltage boosting other than the booster converter, it can be included in the scope of the DC-DC converter in this embodiment.

<Comparative Example>

Fig. 3 is a circuit configuration diagram showing an existing power factor improving circuit in contrast to the power factor improving circuit of Figs. 1 and 2. Fig. 4 is a circuit diagram showing a power factor improving circuit compared with the power factor improving circuit of Figs. to be.

3, the conventional power factor correction circuit has the same input stage circuits as the input stages 110 and 210 described in FIGS. 1 and 2. However, unlike the output stages 120 and 220 of FIGS. 1 and 2, And only one electrolytic capacitor 10 is formed in the electrode 10A.

If only one electrolytic capacitor 10 is formed at the output stage 10A, there is a possibility that the reliability of the charger is lowered and the EMC problem is caused due to the reduction of the current stress of the PFC output electrolytic capacitor and the lack of measures for improving the EMC.

On the other hand, the output stage 20A of the power factor correction circuit shown in FIG. 4 includes the output electrolytic capacitor 121 and the non-electrolytic capacitor 122 connected to the both sides of the electrolytic capacitor 121 described in FIGS. 1 and 2, Between the electrolytic capacitor 121 and the non-electrolytic capacitor, the first inductor 123 and the second inductor 123 may be formed of one inductor 20A different from the coupled inductors 123 and 223 of FIGS.

In this case, it is confirmed that noise phase difference occurs between (+) and (-) of high voltage link due to one inductor (L, 20A) and commom-mode noise caused by this causes serious EMC problem Respectively.

Therefore, the power factor improvement circuit implemented in Fig. 1 and Fig. 2 can reduce the ripple current (current stress) and solve the EMC problem in comparison with Figs. 3 and 4 described above.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the exemplary embodiments or constructions. You can understand that you can do it. The embodiments described above are therefore to be considered in all respects as illustrative and not restrictive.

The embodiments can be applied to EV (Electric Vehicle), HEV (Hybrid Electric Vehicle), PHEV (Plug-in Hybrid Electric Vehicle), FCEV (Fuel Cell Electric Vehicle) and BEV (Battery Electric Vehicle).

100: Power factor correction circuit 110, 210:
120,220: Output stage 121, 221: Electrolytic capacitor
122, 222 non-electrolytic capacitors 123, 223 first inductor

Claims (11)

Input stage; And
And an output terminal connected to the input terminal for improving a power factor through the input terminal,
Wherein,
A non-electrolytic capacitor is formed on both sides of an output electrolytic capacitor, and a first inductor is formed between the non-electrolytic capacitor and the electrolytic capacitor. The method according to claim 1,
Wherein,
Wherein the input power supply, the second inductor, the diode, and the IGFET circuit are configured and connected in series-parallel between the configurations. The method according to claim 1,
Wherein the non-electrolytic capacitor is a film capacitor or a ceramic capacitor. The method according to claim 1,
Wherein the first inductor is coupled at both sides of the electrolytic capacitor, respectively. The method according to claim 1,
Wherein the non-electrolytic capacitor and the first inductor are connected in parallel. An automotive charger for charging a high voltage battery,
A power factor correction circuit having an input terminal and an output terminal connected to the input terminal and having an output terminal for improving the power factor through the input terminal; And
And a DC-DC converter connected to the output terminal for converting a first DC voltage including a sinusoidal wave output from the power factor correction circuit into an AC voltage and converting the converted AC voltage to a second DC voltage,
Wherein,
Forming non-electrolytic capacitors on both sides of an output electrolytic capacitor, and forming a first inductor between the non-electrolytic capacitor and the electrolytic capacitor. The method according to claim 6,
Wherein,
Wherein the input power supply, the second inductor, the diode, and the IGFET circuit are configured and connected in series-parallel between the configurations. The method according to claim 6,
Wherein the non-electrolytic capacitor is a film capacitor or a ceramic capacitor. The method according to claim 6,
Wherein the first inductor is coupled at both sides of the electrolytic capacitor, respectively. The method according to claim 6,
Wherein the DC-DC converter is a boost converter. The method according to claim 6,
Wherein the non-electrolytic capacitor and the first inductor are connected in parallel.

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